Table of Contents
1. Is Fasting Safe?
2. Will Fasting Help Me Lose Fat?
3. Will Fasting Help Me Build Muscle?
4. What About Fasting and Health?
5. The 5:2 (Fast Diet)
6. ADF (Alternate Day Fasting)
7. The 16/8 LeanGains
8. The Warrior Diet
9. Eat Stop Eat
10. Early Time-Restricted Fasting
11. How To Start fasting (+ Misc tips)
12. The Fasting FAQ
13. Final Thoughts
14. WAIT. THERE’S MORE.
DISCLAIMER The Boring Shit
Blah blah blah, if you die I can’t be held responsible. Oh...I’m not allowed to
say that and I need this written by a Lawyer? Well that sounds fucking lame.
Fine, hold on for a second.
The information presented herein is in no way intended as medical advice or to serve as a
substitute for medical counseling. Rather, as with all exercise and nutrition programs, it is
intended only to supplement, not replace, medical care or advice as part of a healthful
lifestyle. As such, the information should be used in conjunction with the guidance and care
of your physician. You must consult your physician before beginning this program as you
would with any exercise and nutrition program. If you choose not to obtain the consent of
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accept full responsibility for your actions. By utilizing the exercise and nutritional strategies
contained herein, you recognize that despite all precautions on the part of Aadam Ali and
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Yay, LAW! OK. LET’S MOVE THE FUCK ON.
Fasting diets have become extremely popular
over the last few years.
And while fasting as a choice of diet is a fairly new phenomenon, the
act of fasting itself has been around for centuries–the great
philosophers of antiquity like Plato, Seneca, and “The Father of
Modern Medicine” Hippocrates, were all extolling the virtues of
short periods of abstinence from food.
The modern day incarnation of fasting is what’s come to be known
as intermittent fasting or the shorthand, IF: simply, intermittent
fasting is an eating pattern that has the dieter cycle periods of eating
and not eating (fasting). While this concept remains at the crux of
every new fasting diet, where they differ is on the length and setup
of the fasting window.
And as we’ll see, there are quite a few.
Before taking a look at the different fasting diets and protocols, we
should answer a few common questions about fasting.
Is Fasting Safe?
If you’re a healthy individual, fasting is perfectly safe.
With that said, fasting may not be suitable for everyone. You should
avoid fasting if:
● You’re pregnant
● Have low blood sugar
● Have a history of disordered eating
As always, check with your doctor before starting a new diet and
Will Fasting Help Me Lose Fat?
Many fasting aficionados make it seem like fasting has magic weight
loss properties. Unfortunately, there are none and calories still
Meaning, even if you implement fasting but are still eating
too many calories–you won’t lose weight.
In a 2015 systematic review of intermittent fasting research–the
largest study on the topic to date–Seimon et al. compared the
effects of of intermittent energy restriction (aka fasting) to
continuous energy restriction (aka normal dieting) on body weight
and body composition.
The result? Both diet styles resulted in the same outcomes.
In 2018, S undfor et al. published their findings from a year long
study on fasting versus normal dieting. They also found no
difference between the two groups when calories were matched.
So, again, it’s y our total calorie intake that matters most and fasting
can be one way of managing that intake.
For example, pushing your first meal later into the day means you
have more calories to eat at lunch and dinner. When calories are
low, eating 2-3 larger meals versus 5-6 small meals can help with
satiety and be psychologically satisfying.
Fasting also has mild appetite suppressant effects–thought to be
due to the ketone production during the fast–which is obviously
beneficial during a fat loss phase.
Will Fasting Help Me Build Muscle?
If you’re eating in a calorie surplus and engaging in progressive
Is that it?
Yes, that’s it.
No, but, fo’ real doe?
Yes, fo’ real.
It’s important to note that if you’re trying to gain weight, fasting
may make it harder to reach your calorie goals–especially if they’re
freakishly high. So if you struggle to hit your daily calories, then, uh,
y’know–probably don’t fast?
What About Fasting and Health?
While there are a lot of claims made about the health benefits of
fasting, the truth is that most of these studies have been done in
mice, and as a recent review paper notes, “further research in
humans is needed before the use of fasting as a health intervention
can be recommended.”
The Two Benefits of Fasting
Nobody Talks About
Fasting isn’t magic and it doesn’t render the first law moot, but
there are two benefits to fasting that, in my opinion, make it an
1. Helps you differentiate between a ctual hunger and
mental hunger – there’s a tendency to feel a bit of hunger
and immediately rush off to satisfy it. The truth is, this hunger
is more often than not just a habit and not actual hunger.
Fasting for short periods helps you differentiate between the
impulse to eat and actual, physical hunger.
2. Builds Discipline and Mental Resilience – I’ve spoken
about this ad nauseam but I use fasting as a tool to build
mental resilience and control impulse. Learning to sit and not
be controlled by your impulses is going to pay dividends not
only to your dieting goals but other goals, too.
Now, with all of that out of the way–let’s take a look at the popular
fasting diets and protocols.
The 5:2 (Fast Diet)
The 5:2 diet (also known as the ‘Fast Diet’) was created by British
Journalist Michael Mosley.
The 5:2 diet involves five days of normal eating, with “little thought
to calorie control” and two days of calorie restriction: 500 calories
for women and 600 calories for men.
● You don’t have to track calories
● It might suit some people better, psychologically
● As there is no calorie control, there’s a chance of overeating on
your normal days.
● It might not be suited for everyone, especially those with really
● May be hard to stick to for the long run for most people.
Should you do it?
This can work well for people who may not want to track calorie
intake too rigidly. If you do decide to use this approach, just
remember to be mindful of your calorie intake. I’d also recommend
coinciding the fast days with your rest days.
(Alternate Day Fasting)
ADF, or Alternate Day Fasting, was created by Dr Krista Varady.
Varady has been responsible for a lot of the research on fasting and
its implication on humans.
It was her research that inspired the Mosley BBC documentary and
the 5:2 diet.
Well, actually, it was more like this: Varady did a ton of research on
fasting in humans and then Mosley and the BBC came along and
stole her research to create the show and then later write Mosley’s
book–or so claims Ms. Varady–and then Varady was all like fuck
you BBC (probably not her exact words) and then she wrote her own
I know, totes cray.
The setup is simple, you cycle between normal calorie intake and a
reduced calorie fast day. This one day fast, one day feed pattern is
● Because there are more fast days, you can be a bit more
relaxed with calorie intake on your normal days
● Not having to track calories
● Can be quite rigid for most people
● Most are unlikely to be able to stick to this pattern for the long
Should you do it?
I’d generally not recommend this approach. While a small number
of people could potentially see success with it, it’s simply not
something most people can adhere to for the long term.
And the fact that you can reap all the benefits of fasting through less
intensive methods (as we’ll see next), just doesn’t necessitate such
an extreme method.
The 16/8 LeanGains
The LeanGains approach was the brainchild of nutritionist and
personal trainer Martin Berkhan. Popularised through his blog of
the same name, t he LeanGains method of fasting alternates 16
hours of fasting with an 8 hour feed window.
Berkhan was one of the first people to really bring ‘calorie’ and ‘carb
cycling’ to the masses. His theory being that utilising more carbs on
training days, with a lower carb, higher fat intake on rest days you
take advantage of nutrient partitioning for optimising body
While new research is surfacing showing the benefits of calorie and
carb cycling, and recently a study on this exact protocol came out
showing surprisingly positive results on body composition, we’re
still at the very early stages to say anything definitive and the most
pragmatic approach still remains the best one: do what you can
stick to. if you can cycle your calories, do so. If it causes more
anxiety around your diet, just stick to a linear calorie intake.
There are a few ways to set this diet up, and Berkhan has gone into
great detail on how to best use each one depending on your
circumstance–you can view those here.
Generally, you want to fast for a 16 hour window and restrict your
eating window to 8 hours.
I use this approach regularly, keeping the bulk of the fasting
window during sleep. So, if my last meal was 7pm on Monday, I
wouldn’t eat again until 11am on Tuesday.
● The fasting window is not as extreme as the majority of other
fasting diets, so makes it much easier to stick to.
● Designed with physical activity in mind, so works well for
● Due to the consistent eating / fasting window, it provides
structure to people’s day.
● Berkhan recommends that for optimal results training take
place in the fasted state. This can be impractical for people
who can only train later. Though, Berkhan has provided
templates for how to use his method in different scenarios.
● Some people may not want to cycle their calorie and carb
Should you do it?
Out of all the fasting methods, this is perhaps the most practical,
and probably why it’s also the most popular. If you are wanting to
experiment with fasting, I’d recommend starting with LeanGains.
The Warrior Diet
The Warrior Diet was created by Ori Hofmekler and involves a 20
hour fast, followed by a 4 hour feeding window. Generally, you fast
throughout the day and have one big meal at night. The diet being
an imitation of the way ancient warriors, ostensibly, ate.
What makes the Warrior Diet stand out from the rest of the fasting
pack is Hofmekler’s allowance of consumption of a small amount of
fruits, vegetables and protein if desired. While this intake is kept to
a small amount, some contend that due to consumption of food
during the ‘fasting’ window, it isn’t really fasting.
If you’re last meal was at 7pm on Monday, you would not eat until
3-4pm on Tuesday. Then repeat.
Hofmekler has said the goal should be to get down to one (whole)
meal per day.
● There is a very heavy emphasis on eating whole, nutrient-rich,
foods such as fruits and vegetables
● Reducing meal frequency to 1-2 meals per day can help during
a diet when calories are bound to be low
● Works well for people who aren’t hungry during the day,
and/or due to work schedule find it easier to skip breakfast
and eat later in the day.
● Unsustainable for most people.
● Due to the setup, you’re most likely to have to train in the
fasted state, which might not be practical for some.
Should you do it?
This diet would be best suited for those who prefer eating a lower
meal frequency and train later in the day. If you are wanting to
experiment with this approach, it would be best to have 1-2 pieces of
fruit with a protein shake before training and then having the one
large meal post workout.
Eat Stop Eat
The Eat Stop Eat approach to fasting was pioneered by B rad Pilon
and involves a 24 hour fast once or twice per week.
If you’re last meal was at 7pm on Monday night, you wouldn’t eat
again until 7pm Tuesday night.
Apart from the 1-2 weekly 24 hour fasts, the rest of the week you eat
● No need to count calories on normal days
● Can suit some people better psychologically
● Seeing that it’s only two days per week, it won’t impede on
your training and recovery.
● Unlike the 5:2 and ADF diets, you’re consuming zero calories
(outside of calorie-free beverages, coffee, and water) and this
can be pretty difficult for some people to stick to.
Should you do it?
This style of fasting can work very well.
I would recommend easing into it slowly. Start with the LeanGains
method, and slowly increase the hours you spend in the fasted state
until you work your way up to a 24 hour fast. Make sure the day you
do decide to do a 24 hour fast, it’s either a rest day or you’re only
engaging in some light form of activity like yoga, stretching, walking
(Early Time-Restricted Feeding)
This is a fairly new model of fasting that has you consuming all your
calories in a 6-12 hour window, and is the inverse of the 16/8
LeanGains model: you eat breakfast, lunch, and skip dinner.
The premise of eTRF is that we should be eating in sync with the
body’s circadian rhythms; eating when it’s light out and ceasing
eating once its dark.
eTRF is still fairly new, though one recent study published in the
journal of Cell Metabolism found subjects on an eTRF protocol
versus a ‘traditional’ meal timing approach saw huge improvements
in their metabolic and health markers, like:
- Reduced insulin resistance
- Reduced blood pressure
- Decreased levels of oxidative stress
Interestingly, participants improved their health despite being in a
calorie deficit and despite losing weight.
Even more interesting is the fact that both diets were matched meal
for meal so these effects weren’t due to a difference in food quality
With all that said, it’s still important to remember a few things:
● It’s only one study, and so we’ll need to wait and see what
happens as more research comes out on eTRF.
● The study had a very small sample size–only 8 subjects, and
only men were studied.
● The subjects were all obese and prediabetic, so we don’t know
what effect this would have on healthy individuals.
● I thought long and hard on this and I can’t think of any pros to
this approach other than you a) REALLY love breakfast and, b)
you’re a social recluse so it doesn’t matter that you stop eating
● You have a social life and/or a family so skipping dinner is not
How To Start fasting
(+ Misc tips)
If you are wanting to dip your toes into the ascetic world of fasting,
here are some tips:
● Start small – I know how exciting it is to want to start
something new, but I’m gonna need you to chill. Don’t just
jump straight into a 24 hour fast. Start small: Instead of a 16
hour fast, maybe you do a 12 hour fast, this isn’t as bad as it
seems, you’ll be asleep for 7-8 hours of it; then you’ll just need
to fast for another four hours after you wake up. Then once
you’re comfortable with the 12 hour fast, you can push it up to
14 hours, then 16.
● Don’t be so rigid – if you only fast for 15 hours instead of
the planned 16, don’t stress it. It’s not going to make a
difference. To add to this, if for whatever reason you need to
eat (say for work) then eat. Once again: shit isn’t that serious.
● Pick your fasting window – Decide the hours you’re going
to be in the fasted state. This will make things simple and
you’ll be more likely to stick to it; there’s also the e ntrainment
● Adjustment period – there will be a week or two where
your body will be adjusting to the fasting, you’ll feel hungrier
during this time but this is simply because your body is used to
eating at your regular intervals. This will pass shortly and
there’s nothing to panic about.
● Stay Busy – During the fasted state you’ll notice a
heightened sense of concentration and cognition–make use of
this by staying busy. Don’t just sit around brooding about food
because that’ll just make you even hungrier. This is why most
people fast during the morning hours when they’re the busiest.
● Coffee is your friend – coffee and fasting are the Bonnie
and Clyde of the nutrition world. Coffee will help with the
focus and alertness and suppress appetite. And besides it’s
The Fasting FAQ
1. Can I drink water during the fast?
Yup. Any calorie-free beverages are fine; coffee, water, diet drinks,
etc. If you wish to add a splash of milk into your coffee, go for it.
Just remember, though: a splash.
2. I’ve heard fasting will cause metabolic damage?
It won’t. This myth came about after a misrepresentation of the
Minnesota Starvation Study – you know, the same study I spoke
about i n my six-motherfucking-thousand-word article. And seeing
that we’re speaking of studies, in a more recent study, researchers
took 11 healthy individuals and had them only drink water for 84
hours – yes, 3.5 days.
By the end of the 84 hours, the researchers found the participants
metabolic rate had increased by ~14% while they fasted.
Now, before you take this the wrong way and think fasting does the
exact opposite and ‘speeds’ up your metabolism, it doesn’t: the
reason for this increase is due to the release of catecholamines – a
group of chemicals released by the body that allow fat to be
mobilised and released from the fat cells, so you can use it for
energy when you’re hunting sabre-tooth tigers…or, shopping for
your grass-fed Bison at your local supermarket.
Your metabolic rate will eventually return back to normal.
3. Won’t Fasting Make Me Lose Muscle?
As long as you’re not being an idiot–like fasting for an entire
week–and strength training, muscle loss is a non issue.
Thankfully, we have research to support this.
In a 2016 study, researchers examined the effects of strength
training three times per week in combination with fasting.
The researchers split 34 men who already had experience lifting
weights into two groups.
Group 1: the fasting group consumed all their calories in an 8
Group 2: the normal diet group who just ate in a calorie
Both groups consumed the same number of calories (and protein).
At the end of the study, neither group had lost lean mass or
In t his study, obese subjects were randomised to 1 of 4 groups for 12
Group 1: Combination (alternate-day fasting + endurance
Group 2: Alternate-day fasting only
Group 3: Exercise
Group 4: Control
They found the combination group maintained their lean mass
during weight loss.
4. Will *insert food item here* Break My Fast?
If it contains calories–it’ll break your fast.
Though, if you’re adding a splash of milk to your tea or coffee in the
morning, uh, what the fuck are you doing? Milk does not belong in
coffee–drink it black or don’t drink it at all.
5. Can I train Fasted?
If you find that you enjoy training fasted, sure.
But for a lot of people fasted training tends to affect performance
negatively. And some people can become hypoglycemic if they train
So my recommendation is to always consume some food 1-2 hours
before you lift.
6. I’ve heard BCAA’s will break my fast, what the
shit cookie is that about?
Yes, they do.
Besides, BCAAs are pointless. Read t his to learn why.
7. But, isn’t breakfast the most important meal of
‘Most important’? No. Most marketed? Yes.
Allow me to defer to Marion Nestle for this:
“Many—if not most—studies demonstrating that breakfast eaters
are healthier and manage weight better than non-breakfast
eaters were sponsored by Kellogg or other breakfast cereal
companies whose businesses depend on people believing that
breakfast means ready-to-eat cereal.
Independently funded studies tend to show that any eating
pattern can promote health if it provides vegetables and fruits,
balances calories, and does not include much junk food.
For most people, when you eat matters far less than how
much you eat (emphasis mine). If you wake up starving, by all
means eat an early breakfast. If not, eat when you are hungry
and don’t worry about it.”
Talking of studies, t his 2014 study that looked at ‘The effectiveness
of breakfast recommendations on weight loss’ concluded:
“A recommendation to eat or skip breakfast h ad no
discernible effect on weight loss in free-living adults who
were attempting to lose weight.”
This 2016 study and this 2017 study came to the same conclusion.
The biggest benefit of fasting, as I mentioned earlier, is that it helps
people realise nothing bad will happen if they don’t eat for a while.
This realisation often leads to a better understanding of their habits
(“Oh, I was only eating because it was a trained response”).
As with most things, fasting is just a tool. It may work well for you,
it may not. Experiment and see how you feel, if it’s not your thing,
that’s fine–you don’t have to fast.
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